Thermostatic switch



Jan. 13, 1931..v F, E. STOVER 1,788,640

vTHERMOSTATIC SWIVTGH Filed Sept. 6, 192'? 4 Sheets-Sheet 1 NVENTOR FANK LSTOVE'R,

' l A TTORNEYS Jan. 13, 1931.

F. E. STOVER THERMOSTATIC SWITCH 6, 1927 4 Sheets-Sheet 2 Filed Sept.

/NI/ENTOR VLA/14 A TTORNEY Jan. 13, 1931; F. E. sTovER 1,788,640

THERMOSTATIC SWITCH Filed Sept. 6, 1927 4 Sheets-Sheet 3 A TTORNEYS `lan. 13, 1931. F, E, STQVER 1,788,640

THERMOSTATIC SWITCH I Filed Sept. 6, 192'? 4 Sheets-Sheet 4 LW//E/VTOR FRAN K E/STO VER,

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A TTORNE YS Patented Jan.` 13, 1931 PLAT FRANK E. STOVER,v OF SPBINGFELD, OHIO f THEnMosTATIc SWITCHV applicati@ med september e, 1927. serial No. 217,630.

My invention relates to thermostatic switches. j

It is theobject -ofmy invention to provide a thermostatic switch for controlling a circuit in such a manner that the'regulation of the temperature of an enclosure such as an incubator, may be kept constant within a range of one-eighth of a degree. j

It is my object toprovide a switch which is suiiiciently sensitive and at the same time is suliciently powerful to maintain this very minute regulation of temperature. y

It is a further object to provide a yswitch which will not flutter, which operates upon a small amount oftcurrent and which will be positive in action although easily adjustable. f

Referring to the drawings: i

Figure 1 is a side elevation of a switch.v

Figure 2`is a plan view thereof.

Figure 3 is an end elevation from the toggleend.`

Figurev 4 is an end elevation from the thermostat end.

Figure 5 is a bottom y'plan view of` theV thermostat. J Y.

Figure 6 is a sectionthroughgthe control lever and the adjustable connection between the control lever and the switch lever.

Referring to the drawings, l is a -base having a standard 2 carrying a pivot 3 `for pivotally supporting the control lever 4. This control lever is adjustablypositioned in one end thereof beyond the pivot and op` 'erated by the rod 5. YThe rod 5y passes' through a sleeve 6 merging from the bottom of the sleeve and terminating in a spider 7 to which it is connectedat 8. f

This spider is connected tothe bottom of "a plurality of thermostatic discs 9th`e tops of which are connected and held rigidly to another spider 10, carriedon the sleeve 'and pivot 3. i

The remote end of the Vlever 4 carries a V shaped slot 11, in which is mounted ka knife edged sheet of metal 12, that is pivotally Thus a toggle construction is vformed connected" at lto a pivoted upright Q14."`

tween the plate 12 andthe lever 4.

lThe support 14 is pivoted at 15 to the base 1. Adjacent to the plate 14 is a standard v16, in which is supported an adjustableA screw 17, passingthrough the Vplatte 14.,y The screw 17 Vsupports av helical spring'18,

'which is held between the end of the screw and the plate 14 and yieldingly resists movement of the plate 14. Y j

The third'standard 18?* is mounted on the. base 1 and carries at its top an overhanging.

spring finger 19, which engages with the lever is carriedr in a pair of relatively move able plates 30 and 81, which are vieldingly j held toone another by means of the adjust-V ing'screw 32 a helical spring 33 whichv en; gages with one of the kplates and the head of the screw,thus yieldingly holding the lei ver 28 in either open or closed position. The i lever 28 is connected toV a terminal 34. The

lever 28 carries a contact member adaptedutov engage with ya stationary contact member 36, which .is connected to the' .other terminal 37.

Operation Thus the movement of thel thermostats will operate the rod 5 and the toggle levers consisting of the plate 12 and lever 4 openv ing and closing the contact 35 and 36.` The l, connection between the proj ection27 and the washer 25 is a loose connection so thatfthe contactglwill `not be made or broken until knear the endy of the stroke of the togglewar-jJ rangement so that asnap action will be proj vided, which will open and close thefcpn v tact. The'spring 33 will ensure the maintev OFFICE" nance of the lever 28 in either its open or closed position until this sudden action takes place.

The thermostats are arranged in multiple so that while they will only move a limited amount and will be su'flieiently delicate to register a very minute change of temperature, such as a variation of a degree, yet by having a group of them sufficient power will be provided for the operation of the mechanism as described. Y Y,

I desire to comprehend within my invention such modifications as may beclearly embraced within my claims and the scope of f my invention.

Having thus fully described my invention,

what I claim is new and desire to secure byr Letters Patent, is: y

l. In combination, a plurality of iiitercoiiynected thermostatic elements, a common means operated thereby, aconimon suspension means, snapping mechanism operated by the thermostatic elements, a switch mechanism operated by said snap mechanism and means to yieldingly resist the movement of the switch mechanism holding it in open or closed position until the snap mechanism has substantiallyk completed its movement.

2. In combination, a plurality of "hermostatic means, a stationary spiderV for suspending said means from one side, a movable s iderconnected to the other side of said t ermostatic means, a rod connected thereto at one end, and, a movable element connected to the other end of said rod and composing one part of aytoggle, a second movable elementpivoted to said first movable element and forming therewith a snap mechanism over dead center, means to limit the movement thereof in one direction, a switch mechanism to limit the movement thereof in the other direction, said switch mechanism being operated by` said snap mechanism.

3. In combination, a plurality of thermostatic means, a stationary spider for suspending said means from one side, a movable sai'der connected to the other side of said t ermostatic means, a rod connected thereto at one end, a movable element connected to the other end of said rodv and composing one part of a toggle, a second movable element pivoted to said irst mofvable element and forming therewith a snap mechv anism, means for pivotally supporting each of said movable elements mechanisms, means for yieldingly accommodating and resisting the movement of said snap mechanism over deadcenter, means to limit the movement thereof in one direction, a switch mechanism to limit the movement thereof in the other direction, said switch mechanism being operated by said snap mechanism, and yielding` means to resist the movement of said switch mechanism until the snap mechanism shall have substantially completed its movement in either direction.

4. In combination, a plurality of thermostatic means, a stationary spider for suspending said means from one side, a movable spider connected to the other side of said thermostatic means, a rod connected thereto at one end, a movable element connected to the other end of said rod and composing one part of atoggle, a second movable element pivoted to said first movable element and formingtherewith a snap mechanism, means for pivotallysupporting each of said movabley elements, means for yieldingly accommodating and resisting the movement of said snap mechanism over dead center, means to limit the movement thereof in one direction, a switch mechanism to limit the movement thereof in the other direction, said switch mechanism being Operated by said snap mechanism, yielding means to resist the movement of said switch mechanism until the snap mechanism shall `have substantially completed. its movement in either direction, and means to adjust the position between said rod and said lever.

5. In combination, a plurality of thermostatic means, a stationary spider for suspending' said means from one side, a movable spider connectedl to the other side of said thermostatic means, a rod connected thereto at one end, a movable element connected to the other end of said rod and coinposing one part of a toggle, a second movable element pivoted to said iii-st movable element and forming therewith a snap mechanism, means for pivotally supporting each of said movable elements, means for yield- 4ingly. accommodating and resisting the Athe movement thereof in the other direction, said switch mechanism being operated by said snap mechanism, yielding means to resist the movement of said switch mechanism until the` snap mechanism shall have substantially completed its movement in either direction, and means to adjust the connection and relative position between said lever and said switch mechanism.

6. Iii combination, a plurality of thermostatic meansa stationary spider for suspending said ineans fromone side, a movable spider connected to the other side of said thermostatic means, a rod connected thereto at one end, a movable element connected to the other end of said rod and composing one part of a toggle, a second movable element pivoted to said first movable element and forming therewith a snap mechanism, means for pivotally supporting each of said movable elements, means for yieldingly accommodating and resisting the movement of said snap mechanism over dead center,

means to limit the movement thereof in one direction, a switch mechanism' to limit the movement thereof in the other direction, said switch mechanism being operated by said snap mechanism, yielding means to re- 4sist the movement ofsaid'switch mechanism ingly resist the movement of said toggle,

ljaw for engagement with a switch mechanism, the switchy mechanism adapted to move within said jaw and to be moved thereby near the end of the stroke of said toggle mechanism in either direction.

8. In combination, a thermostat, a toggle mechanism operated thereby, means to yieldingly resistv the movement of said toggle means to limit the movement thereof, an adjustable insulated means mounted on said toggle mechanism having a relatively widef'jaw for engagement withk a switch mechanism, the switchmechanism adapted to move within said jaw and to be 'moved thereby near the end of the stroke of said toggle mechanism in either direction, and' yielding means to resist the movement of said switch mechanism until the end of the stroke shall have nearly been accomplished by the toggle mechanism.

9. In combination, a plurality of thermostatic elements equi-distantl disposed from contact member cooperating therewith, and

ymeans Y for connecting an electric circuit to said movable and stationary contact members.

10. In combination, a plurality of thermostatic elements equi-distantly disposed from a common center, means for maintaining said elements in suspended position, means 'for equi-distantly 4and equally connecting to a common center said thermostatic' elements, an operating rod, a rigid platform, a lever pivoted on a standard at one end thereof connected to said rod, a

movable standardV pivoted at the other end of` said platform, a knife edge plate engaging with the jaw on the end of said lever s carried by said movable standard pivotally,

a stationary standard adjacent to said movable standard having an adjusting screw projectedthrough said movable standard, yielding means for engagin with said screw on said movable standard or yieldingly resisting the movement 4of the lever and the knife edge plate over dead center, a third stationary standard, means carried thereby for limiting the movement of said lever in one direction, insulated means mounted on said lever having a jaw, a rocking switch arm carrying a contact member adapted to move within said jaw and to be actuated thereby, a stationary contact member cooperating therewith, means for connecting an electric circuit to said movable and stationary contact members, and yielding means for resisting the movement `of said switch mechanism until it shall have been suddenly moved into engaging or disengaging position by the action of said lever.

In testimony whereof, I afx my signature. i v

FRANK E. STOVER.

pivoted at the other end y-`ofsaid platform, g i

a knife edge plate engaging with the jaw on the end of said levercarried by said movable standard pivotally, a stationary standard adjacent to said movable standard having an adjusting screw projected through said movable standard, yielding means for engaging with said screw on said movable standard for yieldingly resisting the movement of the lever and the knife edge plate over dead center, a third-'stationary standard, means carried thereby for'limiting the movement of saidlever in one direction, insulated means mounted on said lever having a jaw, a rocking Vswitch arm carrying a con'- tact member adaptedto move within said jaw and to be actuated thereby, a stationary 

